1. Field of the Invention
The present invention relates to connectors that fluidly connect highly elastic, highly compressible tubing used with implantable devices; and in particular, the present invention relates to connectors that fluidly connect tubing in hydraulic implantable penile prostheses.
2. Description of the Prior Art
Sexual impotence caused by failure to achieve erection of the penis is a common problem. When the impotence is organic in origin, surgeons have attempted to duplicate the function of the erectile tissue (coropora cavernosa) in the penis by way of surgically implanted prostheses. The function of the penile prosthesis is to provide an artificial erection.
One type of penile prothesis presently being used is a hydraulic-type prosthesis having a generally tubular-shape member with flexible walls for implantation in the corpora cavernosa. The prosthesis is inflated by using a fluid drawn from a reservoir. As the prosthesis is inflated, the penis changes from a flaccid state to an erect state, mimicking normal erection. Several prior art hydraulic prostheses for implantation in the corpora cavernosa are described in the following patents: Strauch et al U.S. Pat. No. 3,853,122, Uson U.S. Pat. No. 4,009,711, Finney et al U.S. Pat. No. 4,201,202, Yamanaka U.S. Pat. No. 4,235,227, Finney U.S. Pat. No. 4,318,396, Buck U.S. Pat. No. 3,954,102 and in the articles entitled "An Implantable Fluid Transfer System for Treatment of Impotence," in the Journal of Biomechanics by Kothari, Timm, Frohrib, and Bradley, vol. 5, pp. 567-570, Nov. 1972 and "Management of Erectile Impotence, Use of Implantable Inflatable Prosthesis," in Urology by Scott, Bradley and Timm, Volume II, Number 1, pp. 80-82, July 1973. In addition, in the application entitled, "Penile Prosthesis Device," filed on even date with the present application, a unique hydraulic penile prosthesis device is described.
In the more recent embodiments of inflatable prostheses, the fluid used to inflate the prosthetic member is transferred from a reservoir through tubing to the prosthetic member. It is desirable that the several elements, such as the reservoir, pump and prosthetic members be implanted separately. Typically, sections of elastic tubing are permanently attached to each of the elements. These sections of tubing must then be attached to each other to fluidly connect the several elements after the elements have been implanted.
The tubing used in implantable devices is typically highly elastic and highly compressive. One method of connecting such tubing is to connect each free end of the tubing sections to a rigid connector. The tubing is pushed and expanded over the connector body with the fluid passages of the tubing communicating through the fluid passage of the connector. One such connector being presently used in connecting highly elastic, highly compressive tubing sections is a stainless steel connector having a constant diameter with ends having a rounded annular protrusion. Ends of the tubing sections are slid over the connector and sutured together. There are several problems with such a connector system. First, the tubing varies in quality from batch to batch and the physician must adjust the suturing technique to the variability of the tubing. Second, suturing of the tubing to connect the tubing sections increases the time of the implantation which is undesirable. Third, hydraulic pressurization of the tubing results in radial and longitudial expansion of the tubing which increase the diameter and reduce the wall thickness of the tubing. Suturing of the tubing can be ineffective because the tubing is held on the connector by a narrow band of force which is intended to restrain movement of the tubing on the connector. The suture does not prevent the increase in diameter of the tubing adjacent the suture nor the reduction of wall thickness at the suture which results in reduced radial compressive forces applied by the tubing against the connector. The combination of reduced gripping due to reduced compressive forces and the longitudinal forces in the tubing can drive the tubing free off the connector.
Conventional clamping devices that compressively clamp tubing against a connector also have been found to be unsatisfactory for extended periods of time. Since the tubing is highly compressive along with being highly elastic, conventional clamps, regardless of the compressive force produced, still allow tubing to "creep" off the rigid connector over an extended period of time. If the tubing "creeps" off the connector, unnecessary surgery is required to correct the situation.